The digestive tract of a living body extends from the mouth to the anus, with the esophagus, stomach, small intestine (divided into the duodenum, jejunum and ileum) and large intestine being connected in the order named between them. It is conventional practice for doctors to observe the inside of the digestive tract with an endoscope and perform a treatment such as hemostasis or excision of a polyp inside the digestive tract. However, targets for observation and treatment are limited to regions relatively close to the mouth or anus which is an insertion region of an endoscope. More specifically, when the doctor is to insert the endoscope through the mouth, a target range for observation or treatment includes up to the stomach and part of the duodenum. When the doctor is to insert the endoscope through the anus, a target range for observation or treatment includes up to the large intestine.
As conventional techniques for practicing the above observation and treatment, there are available an upper digestive tract endoscope training simulator simulating the esophagus, stomach and part of the duodenum of the living body (Japanese Patent Laid-Open No. 61-213877 “Endoscope Training Internal Organ/Digestive Tract Simulator”) and a large intestine endoscope training simulator simulating organs from the anus to the large intestine of the living body (Japanese Patent Laid-Open No. 58-192523 “Large Intestine Endoscope Insertion Trainer”). The doctor can use these simulators to practice the operation of the endoscope.
Patent Reference 1: Japanese Patent Laid-Open No. 61-213877
Patent Reference 2: Japanese Patent Laid-Open No. 58-192523
Recently, by making improvements to conventional endoscopes, a balloon endoscope has been developed, which can be inserted into the small intestine (the jejunum and ileum, in particular) as the organ of the digestive tract, which is located farther from the upper digestive tract and large intestine, through the mouth or anus. This makes it possible to observe the inside of the small intestine and perform treatment such as hemostasis or excision of a polyp inside the small intestine. Accompanying this, demands have arisen for training simulators for practicing the insertion of an endoscope into the small intestine and operating it.
On the other hand, a capsule endoscope is on the market, which is swallowed through the mouth for the purpose of observing the small intestine. This capsule endoscope gives little pain to the patient at the time of use. This capsule endoscope, however, has disadvantages such as allowing only observation, incapability of treatment such as hemostasis or excision of a polyp or biopsy, and incapability of being used for a patient suspected to have obstruction or constriction of the intestinal tract. For this reason, capsule endoscopes have not replaced conventional endoscopes. These two types of endoscopes are thought to be selectively used in accordance with purposes in the future.
The small intestine is located deeper than the organs into which an endoscope has been inserted, and is itself a winding hollow organ. It is therefore very difficult to insert an endoscope into the small intestine and advance it to a target region even by using a balloon endoscope or the like which has recently been developed. For this reason, if an unskilled person operates the endoscope, he/she may not achieve an object because of incapability of observing a sufficiently large range of the small intestine. Furthermore, because of dangerous operation, he/she may damage the intestinal tract. Therefore, there has been a need for a training simulator for practicing the operation of inserting an endoscope into the small intestine.